John Denham, the shadow business secretary, gave a strongly worded speech on jobs and growth this morning. Building on Labour's critique of plans to eliminate – rather than halve – the deficit over four years, he attacked the coalition's broader approach to growth. But for this analysis to have any impact, Labour will require a clear plan of its own. The party's positions on job losses, investment, regional growth, and business tax are just some of the areas that need urgent development.

Denham began his speech by outlining that "as a result of a series of wrong choices by this government, the signs are that 2011 will feel like a tough year for families and business up and down the country." Criticising what has been forecast to be the "slowest recovery in 40 years", Denham reiterated research from the Chartered Institute of Personnel and Development showing that there would be a 200,000 fall in employment this year. He concluded by saying "The government has taken a series of decisions which I think will have undermined business confidence and the likelihood of investment."

Turning to his party's own approach, Denham outlined that "public policy must be focused relentlessly on creating the conditions for growth" before defending Labour's approach to "education, transport, infrastructure and broadband" and its belated adoption of an active industrial policy. But when asked during the Q&A to set out more detail on a range of policy areas, Denham argued that the party would not be rushed to decisions but needed to use its policy review process to "understand what was working, what wasn't working, and how is the world going to be different in a few years time".

All this may seem reasonable enough but it leaves a series of unanswered questions about the party's direction of travel.

First, how would job losses be ameliorated? The Labour party's own approach to deficit reduction – cuts of £52bn over four years rather than £83bn – would still cause increased unemployment across both the public and private sector. Would Labour restore the now scrapped Future Jobs Fund and, if so, would it have enough resources to deal with job losses?

Second, in the face of necessary deficit reduction, how would the party seek to increase levels of investment, skills spending, and support for innovation? In October, Alan Johnson set out plans to raise an additional £3.5bn from the banks to offset cuts in infrastructure investment and to support growth. But Labour only proposes to extend the bankers' bonus tax by one year, while the impact on jobs and infrastructure will continue for some time to come. What other tough choices is Labour prepared to make on spending to ensure that its plans have fiscal credibility?

A senior member of the Liberal Democrats told me recently that the Treasury and the Department of Energy and Climate Change are embroiled in a row over whether the green investment bank will be allowed to raise £6bn initially from the bond market or the more modest sum of £2bn. Changes to the fiscal rules may be necessary to bring British accounting of borrowing for commercial purposes into line with the rest of Europe. Will Labour make the case for additional investment now to help boost growth later and speed up Britain's transition to a low-carbon economy?

Third, will Labour policy seek to restore regional development agencies or build on the government's new local enterprise partnerships? Denham criticised LEPs for having no "statutory powers or finance" but the policy has also been praised, for mapping support to economic geographies rather than administrative regions. Related to this, Denham criticised planning reforms that have given more power to local communities. But Labour needs to accept that the future is localist, and develop its economic policies accordingly – starting by backing city-region mayors to drive growth and regeneration outside the South East.

Finally, it's worth noting that apart from a brief mention of R&D tax credits, Denham's speech was silent on the issue of business taxation. At a cost to the Exchequer of £2.7bn, George Osborne intends to reduce corporation tax from 28p to 24p over four years. Meanwhile, the national insurance increase announced by Alistair Darling is being largely implemented while capital gains tax – owing to pressure from the Liberal Democrats – is being raised to 28%. Are cuts to corporation tax the best way to bring about a permanent increase in private investment relative to GDP – which is so crucial for medium-term growth? Is this the right mix of changes, or just an exercise in giving with one hand while taking away with the other? What impact will these policies have on job creation and giving wannabe entrepreneurs the incentive to set up a business?

It is early days for Labour in opposition. But coherence depends on having a credible platform from which to criticise the government. Labour is still some way from having its own strategy on jobs and growth.